from django.http import HttpResponse, Http404, HttpResponseRedirect
from django.shortcuts import render, get_object_or_404

# Create your views here.
from django.template import loader
from django.urls import reverse
from django.views import generic

from polls.models import Question, Choice

''' FBV 函数视图 '''
def index(request):
    # return HttpResponse('投票站点')

    # latest_question_list = Question.objects.order_by('-pub_date')[:5]
    # output = ','.join([q.question_text for q in latest_question_list])
    # return HttpResponse(output)

    # latest_question_list = Question.objects.order_by('-pub_date')[:5]
    # template = loader.get_template('polls/index.html')
    # context = {
    #     'latest_question_list':latest_question_list,
    # }
    # return HttpResponse(template.render(context,request))
    latest_question_list = Question.objects.order_by('-pub_date')[:5]
    context = {
        'latest_question_list':latest_question_list
    }
    return render(request,'polls/index.html',context)


def detail(request,question_id):
    # return HttpResponse(f'在看问卷{question_id}')
    try:
        question = Question.objects.get(pk=question_id)
    except Question.DoesNotExist:
        raise Http404("Question does not exist")
    return render(request,'polls/detail.html',{'question':question})


def results(request,question_id):
    # return HttpResponse(f'问卷结果{question_id}')
    question = get_object_or_404(Question,pk=question_id)
    return render(request,'polls/results.html',{'question':question})

'''  CBV 类视图  '''

class IndexView(generic.ListView):
    template_name = 'polls/index.html'
    context_object_name = 'latest_question_list'

    def get_queryset(self):
        """Return the last five published questions."""
        return Question.objects.order_by('-pub_date')[:5]


class DetailView(generic.DetailView):
    model = Question
    template_name = 'polls/detail.html'


class ResultsView(generic.DetailView):
    model = Question
    template_name = 'polls/results.html'


# def vote(request,question_id):
#     # return  HttpResponse(f'投票结果：{question_id}')
#     question = get_object_or_404(Question,pk=question_id)
#     try:
#         select_choice = question.choice_set.get(pk=request.POST['choice'])
#     except (KeyError,Choice.DoesNotExist):
#         return render(request,'polls/detail.html',{
#             'question':question,
#             'error_message':'选择错误'
#         })
#     else:
#         select_choice.votes += 1
#         select_choice.save()
#         # 重定向
#         return HttpResponseRedirect(reverse('polls:results',args=(question.id,)))

def vote(request, question_id):
    question = get_object_or_404(Question, pk=question_id)
    try:
        selected_choice = question.choice_set.get(pk=request.POST['choice'])
    except (KeyError, Choice.DoesNotExist):
        return render(request, 'polls/detail.html', {
            'question': question,
            'error_message': "You didn't select a choice.",
        })
    else:
        selected_choice.votes += 1
        selected_choice.save()
        return HttpResponseRedirect(reverse('polls:results', args=(question.id,)))
